The present invention relates to a magnetic head slider in which measures are taken for reducing damage to a disk recording medium that could otherwise be caused when the magnetic head slider comes into contact with the disk recording medium as a result of vibration of the slider produced from disturbance. The present invention also relates to a disk drive mounted with the magnetic head slider.
A magnetic disk drive uses a magnetic head slider that flies above a spinning disk recording medium, while maintaining a microscopic distance (a flying height) therefrom. In general the magnetic head slider is provided at its trailing end with a magnetic transducer for reading and writing information from and to the disk recording medium. The magnetic disk drive is required to offer an even higher bit (recording in a circumferential direction) density and a track (recording in a radial direction) density to increase data storage capacity. Techniques for achieving a higher bit density include a technique in which the slider is made to fly above the disk recording medium in as close proximity as possible. To achieve such a stringent requirement for the low flying height, a negative pressure type slider is currently used. The negative pressure type slider offers an outstanding flying stability by making use of negative pressure acting on the slider to attract the slider onto the disk recording medium.
In conventional disk drives, requirements have been based on those for stationary computers. Accordingly, not so considerable importance has been attached to damage to the disk recording medium caused by the slider and arising from slider vibration produced from disturbance. However, there has lately been a rapid spread of notebook computers, portable music players, and the like. Accordingly, with a magnetic disk drive built into such a device, there is a stronger demand for a slider structure that produces only a small slider vibration when the structure is subjected to externally applied vibration and that ensures a stable flying height. There is also a demand for a slider structure that reduces damage to the disk recording medium caused by contact with the slider, occurring as a result of slider vibration.
The magnetic head slider disclosed in Patent Document 1 (Japanese Patent Laid-open No. 2001-14823) is well-known as a technique for reducing damage to the disk recording medium caused by contact with the slider. In the magnetic head slider disclosed in Patent Document 1, an edge portion of the slider includes a buffering layer for absorbing impact, thereby reducing contact damage to the disk recording medium by the slider.
In the magnetic disk slider disclosed in Patent Document 1, however, an alumina buffering layer is used as the buffering layer. The material alumina is softer than the material used for a protective layer or the like on the disk recording medium. Being softer than the protective layer on the disk recording medium and the slider material, the alumina buffering layer is easily deformed. Because of a larger area of contact with the disk recording medium involved during contact, coefficient of friction increases. Consequently, the slider tends to drag as the slider is in contact with a spinning disk recording medium. It is then likely that wear in the buffering layer will progress and the wear will increase the area of contact even further.
The present invention has been made in view of the problems in the prior art described above. It is therefore a feature of the present invention to provide a magnetic head slider capable of reducing damage to a disk recording medium when the slider flying above a disk recording medium inside a magnetic disk drive comes in contact with the disk recording medium due to slider vibration, and a disk drive mounted with such a magnetic head slider.